Are these the coolant drains? 7.4 Horizons (pics)

[Skuza]

Is the silver hex plug in the center of pic the drain plug for the block? There is one on each side and they are not painted and appear to have teflon tape on the threads. Is the sensor with the wires to the left the knock sensor? The dipstick is to the right of the hex plug. I'm gonna be changing the coolant and this info would help.

 

[fc3]

Looks like the coolant drain. Knock sensors usually are near the top of the engine, not the bottom. It's probably an oil pressure sender.

 

[jitts3]

It is the coolant drain. Looks like the sensor is a knock sensor. Some knock sensors listen thru the water jacket. It you pulled it you would get wet.
FYI 1998 Oldsmobile 3.8 uses the block drains for the knock sensor mounting. Must remove to flush coolant.

 

[fc3]

That's interesting. Learn something new every day. My knock sensor is integral to the MEFI-3 processor.

 

[jitts3]

That's interesting. Learn something new every day. My knock sensor is integral to the MEFI-3 processor.

Yea and the framasiat goes to the potanostra at the whatsitalled????? Huh.:lol:
I just know what they are and what they do. From there:huh:.

 

[fc3]

I know how they do what they do. Wanna see on an oscilloscope? Most are piezoelectric devices that generate a small electric current when they get "knocked".

 

[jitts3]

I know how they do what they do. Wanna see on an oscilloscope? Most are piezoelectric devices that generate a small electric current when they get "knocked".

Now you are at my Dad's level. I'm lost now. I don't know if were arguing or not. I'm not agruing. Just saying that on Dad's 1998 Olds they are placed in the block drains. I removed them to flush the cooling system for him. There are 2 on the right side of the engine. As for the osicilloscope, This makes sence now. How they do what they do remaind a mystery till now. COOL Thanks.
Mechanics I'm good at. Elecronics, at your level, I'm lost.:wow:
I do know that not all knock sensors are in the water jacket. Seen them in bell housings on a Dodge.
However I never seen a oil pres. sending unit look like that. GM V8s I've worked on the oil Pressure sending unit comes out the rear of the engine behind the intake.

Knock sensor

Oil pressure

Long story not critisizing your knowledge especially since I admit I am not in your league in electronics, Just wanting to avert a war of words that I have no reason to start. Just misunderstanding the written words. Meaning, Can't hear the tone in ones voice, by typing.:thumbsup:

 

[J Levine]

The knock senders on my 454's look just like this but the holes they are threaded into do not go all the way into the water jacket. You have to remove the block drains as shown in your picure to drain the blocks. Been there and done that.

 

[jitts3]

The knock senders on my 454's look just like this but the holes they are threaded into do not go all the way into the water jacket. You have to remove the block drains as shown in your picure to drain the blocks. Been there and done that.

OK, That settles it. I'm right and wrong. Oh boy. :smt089

 

[fc3]

Not disagreeing with you. I never saw a sensor mounted low. Sorry about the confusion. You provide good info from someone who actually turns a wrench, which is refreshing when contrasted to some who only turn pages in a magazine, but believe that makes them an expert.

Best regards,
Frank

 

[SeaHarley]

I just did this job on my boat. Twin 5.7, 350 mags, MPI.
On mine, they are the knock sensors and I did not have that additional drain plug.
Wish I did!
So I had to remove the knock sensors to drain the block.
That means, at least on mine, the knock sensors are into the water side.

 

[J Levine]

I just did this job on my boat. Twin 5.7, 350 mags, MPI.
On mine, they are the knock sensors and I did not have that additional drain plug.
Wish I did!
So I had to remove the knock sensors to drain the block.
That means, at least on mine, the knock sensors are into the water side.

Thats interesting, must be a small block vs big block thing

 

[Asureyez]

Strange for a drain.

 

[jitts3]

Not disagreeing with you. I never saw a sensor mounted low. Sorry about the confusion. You provide good info from someone who actually turns a wrench, which is refreshing when contrasted to some who only turn pages in a magazine, but believe that makes them an expert.

Best regards,
Frank

Thanks. Just wasn't wanting to ruffel feathers. I know what you mean. My father always said about certain people. They live life by this saying "If you can't dazzel em with intelligence, baffel em with bullcrap." Not me.

Strange for a drain.

Think in the case of Dad's Oldsmobile they figured "why re-tool to make new blocks. This will do." After all the coolant doesn't care what holds it back.

 

[dpmulvey]

Horizon's should have blue plastic "wing" nuts for full drainage and flushing. Beyond that, the drain is pneumatic.

 

[Newbie]

Horizon's should have blue plastic "wing" nuts for full drainage and flushing. Beyond that, the drain is pneumatic.

Um, isn't that for the raw water system? We're talking antifreeze here.